Grinding machine



1931- T. c. SHEEHAN 1, 6

GRINDING MACHINE Original Filed Jan. 24, 1925 2 Sheets-Sheet 1 1-931. T. c. SHEEHAN GRINDING MACHINE Original Filed Jan. 24, 1923 2 Sheets-Sheet 2 INVENTOR I WM;

1 .4 TTORNE Y latented Dec. 29, 1931 NEETE STATES PATENT OFFICE THOMAS CORNELIUS SHEEHAN, OF UPPER MONTCLAIR, NEW JERSEY, ASSIGNOR TO WADE & BUTCHER CORPORATION, OF JERSEY CITY, NEW JERSEY, A CORPORATION OF NEW JERSEY GRINDING MACHINE Application filed January 24, 1923, Serial No. 614,598. Renewed September 29, 1928.

This invention relates to an improvement in grinding machines, more particularly to machines for grinding the bolsters of table knives or other work which is oval in cross section, and it has for its main object the production of a device operating to symmetrically, rapidly and cheaply grind oval articles. lVith this and other objects not specifically mentioned in view, the invention consists in certain constructions and combinations which will be hereinafter fully described and then specifically set forth in the claims hereunto appended.

In the accompanying drawings, which form part of this specification and in which like characters of reference indicate the same or like parts, Fig. 1 is a central sectional elevation of a device constructed in accordance with the invention; Fig. 2 is a fragmentary front endview of the device shown in 1; Fig. 3 is a fragmentary rear end view of the device shown in Fig. 1; Figs. 4, 5, 6 and 7 are diagrammatic views illustrating the operation of the device; and Fig. 8 is an illustration of a table knife blade and a diagrammatic illustration of two different abrasive wheels used in grinding the bolster of said knife blade.

In carrying the invention into effect, there is provided means for rigidly holding and rota ing the work on its longitudinal axis, means for circumferentially grinding the work, and means for producing a relative operating movement of the holding means and the grinding means, which movement is the resultant of a relative rotating movement and a relative orbital movement, it having been discovered that such a relative movementof the work holding means (and of course of the work held thereon) and the grinding means, results in symmetrically, rapidly and cheaply grinding the bolsters of knife blades. In the best constructions, the grinding means operates in a fixed position while the work holding means is given the operating movement above referred to; dual grinding means is employed for the reason that a knife bolster has two plane surfaces and one concave surface, and means is provided for selectively moving said duel grinding means to cause one of the wheels to act on the work while the other is not acting thereon; the work holding means is a rotating chuck eccentrically journaled in a rotating sleeve; gearing is provided for rotating the chuck and sleeve at different speeds in accordance with the ovalness of the work; and means is provided for changing the position of the driving gearing when one grinding wheel is thrown out of action and the other is thrown into action. All of the above mentioned means, parts and devices may be widely varied in construction within the scope of the claims for the device selected to illustrate the invention is but one of many possible concrete embodiments of the same. The invention therefore is not to be restricted to the precise details of the structure shown and described.

Referring to the drawings, 9 indicates the main frame of the machine. Proj ectinp; from the front of said frame is a dovetailed bracket 10 upon which is mounted a dovetailed table 11 adapted to be moved back and forth on the bracket 10 by means of a crank actuated adjusting mechanism 12 of well known character. The table 11 is provided with a transverse slot 13 in which is mounted a slide 14 havinga rack 15 on the under side of one of its ends, this rack being in engagement With a pinion 16 actuated by a shifting lever 17. At one end of the slide 1 1 is mounted a standard 18 supporting in a well known manner an abrasive wheel 19 having a rounded edge and driven by means of a belt 20 from an overhead line shaft, not shown. Similarly, at the opposite end of the slide 14 is mounted a standard 21 supporting in a well known manner an abrasive wheel 22 having a cylindrical edge and driven by means of a belt 23 from an overhead line shaft, not shown. The structure so far described provides means whereby the two abrasive wheels 19 and 22 may be moved to and from the main frame 9 and to and from a point between the two wheels so that they may be'selectively moved to cause one of them to act upon work interposed between the two abrasive wheels.

For the purpose of holding work, in this case a table knife blade, in'order that its bolster may be ground, there is provided a chuck consisting of two lower jaws 24 and 25, and one upper jaw 26, a recess 27 adapted to receive a knife blade being formed by a portion of the adjacent surfaces of the jaws. The front end of each jaw terminates in a tapered head 28 engaged by a sleeve 29 surrounding the major portion of the jaws and carrying at its rear end a gear 30 by means of which it is rotated. Throughout the greater part of their length, the jaws are not held together but at the rear end they are held together by means of a nut 31. Threaded into the rear end of the chuck is arod 32 projecting through to the rear end of the machine. This rod carries a collar 33 and one end of a spring 34 bears against this collar. The other end of the spring bears against a cap 35 secured in the rear end of the sleeve 29 before referred to. The extreme rear end of the rod 32 is threaded and provided with a pair of adjusting nuts 36. The tendency of the spring 34 is to move the jaws of the chuck forwardly and permit them to spread to release a knife in the recess 27. To hold the jaws in closed position there is provided a chuck mechanism including a pair of oppositely disposed jaws 37, the rear end of which contacts with the inner adjusting nut 36. Each jaw 37 has a short prong 38 engaging a depression 39 formed in a split sleeve 40 embracing the rod 32. Each jaw 37 also has a "long prong 41 working in the split sleeve 40. When the clutch is in operation to hold a knife blade securely in the chuck, the extreme ends of the prongs 4141 are held in the position shown in Fig. 1 by means of a clutch keeper 42 having an annular groove 43 engaged by studs 44 on a. clutch shifter 45 of well known construction. When the knife is to be released, the keeper 42 is moved to the rear; that is, to the left in Fig. 1, until the ends of the long prong 41 are free. The spring 34 then acts to move the chuck forwardly so that the tapered head 28 of each jaw becomes disengaged fromthe correspondingly tapered end of the sleeve 29. NVhen this occurs, the chuck jaws become relatively movable and the knife blade may be easily withdrawn from the recess 27, and another onesubstituted; whereupon the keeper 42 is then moved in the opposite direction. as to the right in Fig. 1, to compress the spring 34 and move the chuck bodily to the left, there by causing the jaws 24,25 and 26 to clamp the new knife blade in the recess 27. The chuck as a whole is eccentrically mounted in a sleeve 46 which carries a pulley 47 driven by a belt 48 from an overhead line shaft, not shown. The sleeve 46 is journaled in suitable bearings 4949 in the main frame 9 of the machine, and at its rear end it carries a pinion 50. This pinion 50 is in mesh with a back gear 51 loosely mounted on a sleeve 52 secured in the upper part ofthe frame 9 and extending from the front of the machine to the rear, and in the rear projecting beyond the frame 9. Also mounted on the sleeve 52 is another back gear 53 held in place on the sleeve by means of a collar 54. The back gear 53 is in mesh with the gear 30 before referred to. The purpose of the gearing is to transmit motion from the pulley and belt driven sleeve 46 to the chuck sleeve 29; and to effect this result, both back gears being loose on the sleeve 52, there is provided a coupling pin 55 .engageable with said back gears at two points on the gear 51; that is, at 56 and at a point 57, 90 degrees from the point 56. The coupling pin 55 is fast to an arm 58, also fast to a rod 59 extending through the sleeve 52 to the front of the machine where it terminates in a knob 60. Between this knob 60 and the front face of the frame 9 is a compression spring 61 operative to hold the coupling pin in engaged position. When it is desired to shift the back gears to cause the coupling pin to engage the gear 51 at, say the point 57, the operator pushes the knob 60 against the action of the spring 61 which causes the withdrawal of the coupling pin 55 from the gear 51. The gear 51 is then moved a quarter turn when the knob is released and the coupling pin will engage the aperture at the point 57 again looking the back gears together. The purpose of this gear shifting will be presently explained. Assuming that a knife blade, the bolster of which is to be ground, has been clamped in the chuck and that it is desired to first grind the concave part of the bolster; the operator actuates the crank 12 to move the table 11 to the rear until the abrasive wheel 19 comes into alignment with the concave part of the bolster. He than raises thelever 17 to move the slide 14 to cause the concave edged abrasive wheel to act on the work. Then as the sleeve 46 is rotated by means of the pulley 47 and belt 48, it produces an orbital movement of the chuck owing to the eccentric mounting of the latter in the former; and through the agency of the back gearing it also rotates the chuck but at half speed, the ratio of reduction of the gearing being 1 to 2. Thus there is produced a relative movement of the grinding means and of the work holding means which is the resultant of a relative rotating movement and a relative orbital movement. The relative rotative speed of the sleeve 46 and of the chuck eccentrically mounted therein is dependent upon the ovalness of the work to be operated on; and when this varies, the gearing must be changed in accordance with the change of ovalness. In Figs. 4, 5, 6 and 7, the chuck diagrammatically illustrated is indicated by the reference character (1 and the sleeve the reference character S, while the cross section of the bolster to be ground is indicated in each case at B. In Fig. 4, the grinding wheel 19 is in contact with the bolster B at a point at one end of its longer axis.

At this time the chuck C occupies its lowermost position in the sleeve S. As the grinding operation proceeds, the grinding wheel 19 does not move from the fixed position in which it rotates. The chuck C, however, rotates half as rapidly as the sleeve S rotates. lVhen the sleeve S has rotated 90 degrees, the chuck C will have rotated 45 degrees, which brings the bolster in the position shown in Fig. 5, a quartering point thereon being then in contact with the grinding wheel 19. When the sleeve has rotated 180 degrees, the chuck will have rotated 90 degrees, and the bolster will be in the position shown in Fig. 6, still in contact with the grinding wheel 19 but at apoint at one end of its shorter axis. When the sleeve has rotated 270 degrees, the bolster will have rotated 135 degrees and will be in the position shown in Fig. 7, again in quartering contact with the grinding wheel 19. lVhile only four diagrammatic positions are shown, it is to be understood that throughout the rotation of the bolster B its surface is in contact with the grinding wheel 19. When the concave part of the bolster has been ground, the lever 17 is moved downwardly, which results in moving the convex-edged abrasive wheel out of contact with the work in moving the cylindricahedged abrasive wheel 22 into contact therewith, to grind the straight oval parts of the bolster. hen this is done, the point of contact between the work and the grinding medium is changed 180 degrees; that is to say, instead of grinding on the left side of the work, as it would appear in Fig. 2, the grinding is done on the right side of the work. This necessitates changing the relative positions of the chuck C and sleeve S because the abrasive wheel 22 operates on the opposite side of the oval and the position of the bolster must therefore be changed 90 degrees or half the change in grinding position in order to maintain con tact of the bolster with the grinding wheel. This is accomplished by the operation of the coupling pin 55 before described, to turn the chuck over 90 degrees. The operation of the machine shown and described results in precision grinding which greatly improves the appearance of the work and enhances its value at a lower cost of production.

l/Vhat is claimed is:

1. A machine for grinding oval knife bolsters, comprising mechanism for rigidly holding and producing a parallel flying movement of the bolster that is the resultant of a rotating movement on its own axis and an orbital movement about a parallel axis, grinders selectively operative in stationary position at different sides of the bolster, and means for selectively timin said flying movement to keep the bolster in contact with the selected grinder.

2. A machine for grinding oval knife bolsters, comprising mechanism for rigidly holding and producing a parallel flying movement of the bolster that is the resultant of a rotating movement on its own axis and an orbital movement about a parallel axis, grinders selectively operative in stationary position at different sides of the bolster, and means for selectively timing said flying movement to keep the bolster in contact with the selected grinder, said mechanism including knife blade holding means in engagement with the blade substantially throughout its length.

3. A machine for grinding oval knife bolsters, comprising mechanism for rigidly holding and producing a parallel flying movement of the bolster that is the resultant of a rotating movement about its own axis and an orbital movement about a parallel axis, grindrs selectively operative in stationary position at different sides of the bolster, and means for selectively timing said flying movement to keep the bolster in contact with the selected grinder, said mechanism including a chuck having two quarter-sections provided with knife blade engaging rabbets and one half-section provided with a blade engaging tenon coacting with said rabbets.

4. A machine for grinding oval knife bolsters, comprising mechanism for rigidly holding and producing a parallel flying movement of the bolster that is the resultant of a rotating movement about its own axis and an orbital movement about a parallel axis, grinders selectively operative in stationary position at different sides of the bolster, and means for selectively timing said flying movement to keep the bolster in contact with the selected grinder, said mechanism including a multiple aw chuck for engaging a knife blade and a nut for holding the jaws in proper cooperative position.

5. A machine for grinding oval knife bolsters, comprising mechanism for rigidly holding and producing a parallel flying movement of the bolster that is the resultant of a rotating movement about its own axis and an orbital movement about a parallel axis, grinders selectively operative in stationary position at different sides of the bolster, and means for selectively timing said flying movement to keep the bolster in contact with the selected grinder, said mechanism including a chuck and a clutch normally and rigidly holding said chuck in engagement with the blade of the knife.

6. A machine for grinding oval knife bolsters, comprising mechanism for rigidly holding and producing a parallel flying movement of the bolster that is the resultant of a rotating movement about its own axis and an orbital movement about a parallel axis, grinders selectively operative in stationary position at different sides of the bolster, and means for selectively timing said flying movement to keep the bolster in contact with the selected grinder, said'mechanismincluding a chuck having knife blade engaging jaws provided' with tapered heads, a sleeve surrounding said chuck, and a clutch supported by said sleeve and normally causing said sleeve to act on the tapered heads of said jaws to close them.

"7. A machine for grinding oval knife bolsters, comprising mechanism for rigidly holding and producing a parallel flying movement of the bolster that is the resultant of a rotating movement about its own axis ant an orbital movement about a parallel axis, grinders selectively operative in stationary position at different sides of the bolster, and means for selectively timing said flying movement to keep the bolster in contact with the selected grinder, said mechanism including a chuck, a sleeve surrounding said chuck, a clutch supported by said sleeve and normally causing said sleeve to hold said chuck in rigid engagement with a knife blade, and means for rotating said sleeve.

8. A machine for grinding oval knife bolsters, comprising mechanism for rigidly holding and producing a parallel flying movement of the bolster that is the resultant of a rotating movement about its own axis and an orbital movement about a parallel axis, grinders selectively operative in stationary position at different sides of the bolster, and means for selectively timing said flying movement tokeep the bolster in contact with the selected grinder, said mechanism including a chuck, a sleeve surrounding said chuck, a clutch supported by said sleeve and normally causing said sleeve to hold said chuck in rigid engagement with a knife blade, and change gearing rotating said sleeve.

9. A machine for grinding oval knife bolsters, comprising mechanism for rigidly holding and producing a parallel flying movement of the bolster that is the resultant of a rotating movement about its own axis and an orbital movement about a parallel axis, grinders selectively operative in stationary position at different sides of the bolster, and means for selectively timing said flying movement to keep the bolster in contact with the selected grinder, said mechanism including a chuck engaging a knife blade, a rod extending rearwardly from said chuck, a clutch mounted on the rear end of said rod, a sleeve surrounding said chuck and supporting said clutch, and a releasing spring coiled around said rod within said sleeve and acting to release the blade when said clutch is released.

10. A machine for grinding oval knife bolsters, comprising mechanism for rigidly holding and producing a parallel flying movement of the bolster that is the resultant of a rotating movement about its own axis and an orbital movement about a parallel axis, grinders selectively operative in stationary position at dilferent sides of the bolster, and

means for selectively timing said flying move ment to keep the bolster in contact with the selected grinder, said mechanism including a multiple jaw chuck engaging a knife blade, a nut holding the jaws in proper cooperative position, a rod extending rearwardly from said jaws, a clutch mounted on the rear end of the rod, a collar fast on said rod, a spring interposed between said collar and said clutch, and declutching means.

11. A machine for grinding oval knife bolsters, comprising mechanism for rigidly holding and producing a parallel flying movement of the bolster that is the resultant of a rotating movement about its own axis and an orbital movement about a parallel axis, grinders selectively operative in stationary position at different sides of the bolster, and means for selectively timing said flying movement to keep the bolster in contact with the selected grinder, said mechanism including a chuck engaging a knife blade, a sleeve surrounding said chuck, a hollow shaft in which said sleeve is eccentrically journaled, a belt driven pulley rotating said shaft, and a pinion carried by said shaft for producing the rotating movement of the bolster on its own axis.

12. A machine for grinding oval knife bolsters, comprising mechanism for rigidly holding and producing a parallel flying movement of the bolster that is the resultant of a rotating movement on its own axis and an orbital movement about a parallel axis, grinders selectively operative in stationary position at different sides of the bolster, and means for selectively timing said flying movement to keep the bolster in contact with the selected grinder, said grinders being provided with means for selectively moving them in and out of operative position.

13. In a machine for oval grinding, the combination with a sleeve, of a work holding chuck eccentrically journaled in said sleeve, a gear on said sleeve, a gear on said chuck, a back gear in mesh with said sleeve gear, a back gear in mesh with said chuck gear, and a spring-actuated coupling pin engageable with said back gears at different points.

14. In a machine for oval grinding, the combination with a sleeve, of a work holding chuck eccentrically journaled in said sleeve, a gear on said sleeve, a gear on said chuck, a back gear in mesh with said'sleeve gear, a back gear in mesh with said chuck gear, and means for connecting said back gears in different relative positions.

In testimony whereof, I have signed my name to this specification.

THOMAS CORNELIUS SHEEHAN. 

